walrus

/wawl"reuhs, wol"-/, n., pl. walruses, (esp. collectively) walrus.

a large marine mammal, Odobenus nosmarus, of arctic seas, related to the seals, and having flippers, a pair of large tusks, and a tough, wrinkled skin.

[1645-55; < D: lit., whale horse; c. G Walross, Dan hvalros; cf. OE horshwael horse-whale]

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Only living species (Odobenus rosmarus) of the pinniped family Odobenidae.

Larger than the related seals, walrus males grow up to 12 ft (3.7 m) long and weigh up to 2,800 lbs (1,270 kg). Both sexes have long, downward-pointing tusks that may grow to 3 ft (1 m) long and weigh 12 lbs (5.4 kg) each. They have no external ears. The grayish skin is deeply folded over the shoulders. They live on ice floes, in groups of up to 100, on relatively shallow water in arctic seas of Eurasia and North America. They may dive to great depths in search of food, mostly shellfish. On land and ice, they move on all four limbs. They generally follow the ice line south in winter and north in summer. Traditionally important to native humans as sources of food and clothing, they have also been hunted commercially for centuries, which has resulted in serious depletion of their numbers. Commercial hunting is now generally banned.

Atlantic walrus (Odobenus rosmarus rosmarus)

Francisco Erize/Bruce Coleman Ltd.

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▪ mammal

also called  morse 

 huge, seal-like mammal found in Arctic seas. There are two subspecies: the Atlantic walrus (Odobenus rosmarus rosmarus) and the Pacific walrus (O. rosmarus divergens). Male Pacific walrus are slightly larger, with longer tusks.

      The grayish skin of the walrus is 2–4 cm (1–2 inches) thick, with deep folds around the shoulders. The skin is covered with short reddish hair, giving the animals an overall cinnamon colour. The walrus has a rounded head, small eyes, and no external ears. Its muzzle is short and broad and has a conspicuous moustache of stiff, quill-like whiskers (vibrissae). The male, which reaches a maximum length and weight of about 3.7 metres (12 feet) and 1,700 kg (3,700 pounds), is about a third larger than the female.

 Both sexes possess long tusks (the upper canine teeth) that project downward from the mouth. In the male they can grow to about a metre in length and 5.4 kg (12 pounds) in weight. The tusks function mainly in mating display and in defense against other walrus. They are not used to dig food from the ocean floor. The walrus feeds at depths of less than 80 metres (260 feet), usually at 10–50 metres (30–160 feet). Rooting along the ocean floor with its snout, it identifies prey with its whiskers. The walrus's diet consists largely of clams and mussels but occasionally includes fish and even small seals.

      The walrus is a gregarious animal, living in groups sometimes numbering 100 or more. It does not frequent deep water, instead inhabiting coasts and margins of ice shelves, where it periodically hauls itself onto beaches and ice floes to rest and bask. Like the sea lion and fur seal (family Otariidae), the walrus can turn its hind flippers forward under its body when on land and can thus crawl using all four limbs. Males mate with multiple females in winter. Dominance is established among males according to body and tusk size. They display by showing their tusks and making clicking and bell-like sounds underwater. When a female is attracted, she joins the male, and mating occurs underwater. Delayed implantation of the fertilized egg results in a total gestation of 15–16 months. The single walrus pup weighs about 60 kg (130 pounds) at birth and remains with the female for two to three years. Sexual maturity occurs at six to seven years of age in females, eight to ten years in males. In the wild, walrus can live slightly more than 40 years. On rare occasions they are killed by polar bears or killer whales.

      The walrus is valued by both the and commercial hunters for blubber, hide, and ivory tusks. Its numbers have been reduced by commercial operations. Walrus are now protected from sealers but are still subject to subsistence hunting by aboriginals. Like seals, the walrus is a pinniped. It is the sole living member of the family Odobenidae.

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